module.exports = 
	{
		title: '困难',   // 必要的
    collapsable: true, // 可选的, 默认值是 true,
    sidebarDepth: 1,    // 可选的, 默认值是 1
    children: [
    	'hard/23.first-missing-positive',
    	'hard/81.integer-to-english-words',
    	'hard/95.text-justification',
    	'hard/99.shortest-palindrome',
    	'hard/104.largest-palindrome-product',
    	'hard/112.number-of-digit-one',
    	'hard/119.longest-valid-parentheses',
    	'hard/129.reverse-nodes-in-k-group',
    	'hard/133.merge-k-sorted-lists',
    	'hard/137.longest-consecutive-sequence'
    ]
	}